The importance of this is easy to understand through a minor thought experiment – what would happen if the goalie weren’t there? The defenders who kicked the ball straight to the goalie would score a catastrophic own goal while the defenders who kicked to the right or the left would just put the ball out of play for a corner kick. This is the only factor truly at play when players pass the ball to their own goalies. The players who account for the risk of an own goal pass the ball to the left or the right of the goalie while those who were less mindful of the risk opted to kick the ball straight at their teammate.
As I thought more about these passes, I slowly realized that they demonstrated a player’s understanding of risk better than any other play that could happen during the game. A player who passed the ball straight to the goalie was essentially saying – yeah, something COULD go wrong, but why would it since the goalie’s there, and if it does SOMEHOW go wrong, it would be an accident and therefore nobody’s fault. On the other hand, a player who always played the ball to the left or the right was countering – nothing will probably go wrong but sometimes the goalie slips or the ball takes a weird hop or the goalie is doing something unexpected, so better not to risk losing the game when a tiny fail-safe measure like passing the ball five yards left of the keeper ensures safety.
The most important implication of how a defender passes the ball to his own goalie is what it says about the player’s approach in other more important areas of the game. If I noticed a player consistently passed the ball to the left or the right of his goalie, I would take it as a sign that the player was properly accounting for risk in other aspects of the game. I would be surprised, for example, if such a player was frequently caught out of position or occasionally liable to make a reckless slide tackle that might result in a red card. There is nothing scientific about my conclusion but since defending is essentially the art of minimizing the number of goals conceded, I would be perfectly comfortable reading too much into the way a defender passed a ball back to his keeper.